I have been scrounging through forums looking for a list of possible causes of a transmission to enter limp mode. The truck is a 1996 f150 4x2 (automatic of course) with the 4.9L engine. I bought it off a guy in unknown condition (all I knew was that it did not run). After replacing the starter solenoid, it started up just fine. I have had transmission issues since the day I got it and started driving it. The truck was shuddering quite a bit on take-off and deceleration. Naturally, I tested the TC by giving gas and brake at same time and held rpm down. Changed trans fluid (not recommended I know). Added some friction modifier just to be safe. Friction modifier apparently helped despite (apparently) functional TC. Truck had rough shifting into gear (as in shifting from park to drive and neutral), cleaned MLPS and shifting much smoother. However, when driving, the car is lurching into gear, not entirely sure if it reaches 2nd gear, but it jumps into gear with a noticeable "bump" while driving. Wondering if anyone knows whether I am in limp mode or if I am experiencing something entirely different. Innova 5210 pulled a TPS code (promptly replaced) and a maf sensor code (replaced as well). I have tested all fuses and powertrain relay (all good). All that's left in power control is the powertrain diode. After that I'm stuck on what to test. Sorry for long post, any tips? Also not sure if important but the factory shift lever was replaced with a lever that has no overdrive button (and the od wires in the handle of the shift lever were cut.


1996 F150 (4x2)
E40D
196,000 miles
No Overdrive Shift Lever
VIN: 1FTEF15Y0TLA73378

 

None, because there is no "limp mode" for a transmission - it only works 1 way. The only modes for the EEC (PCM) are: normal, FMEM (Failure Mode Effects Management), & HLOS (Hardware Limited Operating Strategy). Yours is probably in FMEM or normal. This page explains how the E4OD works:

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ALL the truck's details need to be in your signature. Right now, it contains very little useful info. Without losing any, it could be shortened to:
96 4x2 E40D 196Kmi, noTCS
We don't need to see the VIN - we need YOU to decode it all, and type it in plain text using normal abbreviations and no repetition so you can get as much as possible in there. You don't have the engine, trim level, colors, tires, gears, cab/bed sizes, options, mods, miles, maintenance, damage, repairs... Upload an avatar of the truck, and put your location in your profile. This page explains more, and contains a link to a list of standard abbreviations:

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That tests (or breaks) the engine mounts; it doesn't show much about the TC. Did you inspect the mounts? It's EXTREMELY common for them to break, which can cause many noises & vibrations that could be mistaken for transmission problems. Read this page & follow the links on it:

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Changing the fluid is not recommended; adding anything to the fluid is not "safe" - it's specifically forbidden. Friction modifier is only used in the gear oil of a limited slip diff.How, exactly? Did it fail some test that you didn't mention? Did it pass the same test after cleaning?The MLPS has no effect on shifting.Scantools are NOT reliable on these trucks. Ford recommends a jumper wire; read this whole page (a few times, if necessary):

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Codes do NOT mean to change any part, and you should never pick a part name or word out of a code definition. List each code number and its COMPLETE definition from the page I just linked.No, there are dozens of other components in the powertrain; from the radiator to the rear axle.You haven't mentioned TESTING anything yet.The TCS/TCIL have no impact on how the transmission shifts; only in your ability to change that behavior, or to see if there are faults in the EEC that relate to the trans. Browse your local JYs for a replacement - it's relatively easy to swap.

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If you can't find a used one, new are available.

 

How does one test the motor mounts? I’m new to all of this and am just looking for a checklist I need to go down. I’m confused, the code reader has a menu to specify the year, brand, and engine in my car, how would it still have issues identifying the vehicle (just curious). I will rerun the codes today and see what number it pulls and update you.

As for the MLPS I just cleaned the shift linkage connecting to it which made the shifts from the lever much cleaner (not the shifting while driving that is done automatically by the transmission, I know MLPS doesn’t effect that). I also replaced the bushing for the shift lever column by the steering wheel/column.

To clarify I HAVE tested the fuses and relays in the power control box under the hood and by the steering wheel.

1996 F150 XL 4x2
27” tires
White with blue accent (and interior)
4.9L (electronic injection) with the E40D
196k miles
Single Cab with 8’ bed (long bed)
Have replaced TPS, Airbag Clockspring, Both Fuel Pumps and the Rear Fuel Tank
ENGINE COOLANT SENSOR IS MISSING THE WIRE THAT ALLOWS TEMP TO APPEAR IN DASH CLUSTER (engine temp gauge on dash does not work because of this)

 

One way of testing mounts is the way you described testing the TC: have an assistant power-brake the engine while you watch the mounts through the the front wheelwells. Another way is using a prybar. Or a simple visual inspection is often enough to spot the telltale cracks in the rubber & exposed wear surfaces.

Your signature contains more info now, but some unnecessary & redundant. 27" is not a tire size - use what's molded into the sidewall. This is the reduced version now:
96 XL 4x2 bu/wh extr./bu intr. 4.9L E4OD(no TCS) 196Kmi std.cab/8'bed

The ECT sensor does not connect to the gauge; sensors are only for the EEC. Gauges are typically driven by senders.

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Will test engine mounts today and see if bad. I highly suspect that is one issue, but would it really be THE issue? Not a bad place to start anyway. I have checked out my shift linkage while the car was turned on and could visibly see the engine and transmission move a little bit back and forth upon starting, which probably should have been a red flag but I didn't put it together.

As for the coolant "sensor", I misspoke. I did in fact mean the coolant temperature sender that screws into the engine by the exhaust manifold towards the transmission on the passenger side. The wire that "plugs" into the coolant sender is apparently not there, below I am attaching a screenshot of what it supposedly would look like (found in a youtube video, also linked below). I was thinking that while I'm looking at engine mounts, I will replace this (I have the new coolant sender fitting ready, but no wire to connect it to the truck). I can see how the wire connects, but I was wondering if someone could tell me what the other side of the wire connects to so I can track it down if it is in fact still on the truck somewhere (or where it would plug in to replace).



(Note this is a 1995 F150, NOT a 1996 like mine)

96 XL 4x2 bu/wh extr./bu intr. 4.9L E4OD(no TCS) 196Kmi std.cab/8'bed

(Also below is a .pdf file screenshot from the video of the coolant sender connection to the sending unit)

 

The wire is built into the harness, and comes out within 2" of it. Coolant temp wire is R/Wh; oil pressure is Wh/R; they use the same connector to their senders: a rubber-encased right-angle push-on female "bullet" that grips the threads.

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It's above the oil cap in this pic:

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Thank you for those photos. I managed to find it, had come disconnected and was hiding behind the main wiring harness that it exits from. Checked the female elbow connector, no power was getting to it. Turns out the copper sleeve inside it had corroded onto the sending unit. Cut the wire before the ring terminal and put a crush connector ring terminal on it. Replaced the sender and found a lock washer and small nut that threaded onto the threads of the unit. Slid the ring terminal over and tightened the nut onto it. It now sends information to the temp gauge on the dash. Still have to check motor mounts as well.

Off topic, but any tips on steering wheel alignment. Steering wheel was off when I bought it, replaced airbag and now it’s even further off. The airbag wiring from the clockspring to the airbag unit and cruise control on the wheel itself appear to interfere with a proper alignment.

 

The steering column is keyed so it can only be connected 1 way from the wheel down to the steering box. The steering wheel can only be straightened during a full front-end alignment by a pro using an alignment system. I recommend finding a shop with a modern optical machine - preferably a Hunter.

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Before going, buy a pair of adjustable camber cams so you never have to buy fixed cams again. Set them to zero, and keep the instruction sheets in the truck so the alignment tech can read them. Make sure you get them back when he's done.

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